1. Field of the Invention
This invention relates to dunnage and to a method for packaging layers of products in a container without the weight of superjacent products resting or bearing on subjacent products and wherein the products may be readily removed from the container until it is empty, and wherein the empty container with or without the dunnage may returned to the sender for re-use.
2. Background Art
In U.S. Pat. Nos. 5,267,652 and 5,178,279, incorporated herein by reference, dunnage is disclosed for supporting automotive parts or the like for shipment and storage pending use on an assembly line. It is intended that boxes containing the parts, which are supported in the dunnage, are placed adjacent the automotive assembly line, and as vehicles move down the line, the parts are removed from the boxes and placed in or on the vehicle. The dunnage may comprise elongated strips of polyethylene, polystyrene or the like having transverse slots or notches shaped to allow the parts to nestle therein so they do not rub against adjacent parts. This arrangement has been quite satisfactory.
In U.S. Pat. No. 5,267,652, the dunnage for one layer of products rests or bears on surfaces of the products of the subjacent layer, and when such surfaces are the Class A surfaces may result in marring the same. In such cases it is desirable to store the parts in layers in the boxes in such fashion that the superjacent dunnage is spaced from the Class A surfaces of the subjacent parts. On occasion this may be accomplished by designing the dunnage to have upstanding posts, such as shown in U.S. Pat. No. 5,178,279, where upstanding posts serve to hold superjacent dunnage out of contact with Class A surfaces of a subjacent layer.
In some instances the shape of the parts is such that the dunnage disclosed in the '652 patent or the '279 patent cannot be configured in themselves to avoid the dunnage of a superjacent layer from resting on or contacting the Class A surfaces of the parts in a subjacent layer or for any other reason the dunnage of such patents cannot hold the parts out of undesired contact either with other parts, or with the container in which the dunnage and parts are stored.
Recently, particularly in the automobile manufacturing industry, the practice had been growing of using reusable shipping containers or boxes which, after being emptied at the automobile manufacturer, are collapsible and are returned to the parts supplier for refilling and return shipment to the automobile manufacturer. It has therefore become desirable to utilize dunnage which may also be returnable and which can be returned to the parts supplier within the collapsed returning boxes.
Providing dunnage which is usable with collapsible boxes and which itself is returnable for reuse, has required several modifications in the design of the dunnage while still using several of the basic features as described in the parent application as originally filed.